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- Atoms are made from a nucleus of protons and neutrons and a cloud of electrons. 原子是由质子和中子组成的原子核与围绕原子核的电子云构成的。
- Atoms are composed of protons and neutrons in a nucleus surrounded by a cloud of electrons . 原子由中子和质子构成，它们位于核子中，核子又被电子云所包围。
- The reason is that the electron withdrawing and donating of two substituting groups result in the changes in the density of electron cloud of chemical bonds in ortho position. 这是由于两个取代基的吸或供电子引起了相邻化学键的电子云密度发生变化,使旋光度相应变化,从而导致旋光性。
- A cloud of locusts hit the farm. 大群蝗虫袭击了那个农场。
- A cloud of smoke was suspended in the air. 一股烟云飘悬在天空中。
- A cloud of smoke or dust that chokes or smothers. 沙尘弥漫呛人或令人窒息的烟雾或尘土
- A cloud of smoke formed over the burning city. 燃烧的城市上空形成一片烟云。
- The cars set off in a cloud of dust. 那些汽车在滚滚尘埃中启动了。
- The assignment of electrons is somewhat arbitrary. 电子的分配多少带有武断性。
- A cloud of smoke floated over the battlefield. 战场上硝烟弥漫。
- Oxidation involves the transfer of electrons. 氧化过程涉及电子的转移。
- The car raised a cloud of dust as it rushed past. 汽车开过时扬起一阵尘土。
- An electric current in metal is caused by the movement of electrons. 金属内电流是由电子运动引起的。
- She spied a cloud of smoke in the distance. 她发现远处有一团烟。
- A cloud of smoke emitted from the chimney. 一股烟从烟囱里喷出来。
- Atoms are made up of electrons and protons. 原子由电子和质子构成。
- The car raised a cloud of dust as it went by . 汽车走过时扬起一片尘土。
- The chimney blew out a cloud of light smoke. 烟囱里冒出一股青烟。
- The number of electron pairs an atom can share with other atoms. 共用电子对数，共价一个原子与其他原子共用的电子的对数
- A great cloud of dust boiled up past the windows. 一大团尘土旋动着在窗前经过。
